Modular drug delivery system

ABSTRACT

The invention relates to a modular drug delivery system, comprising a reservoir unit and a control unit in combination with at least one further reservoir or control unit, whereby each combination of a reservoir unit and a control provides different capabilities. More specifically, the present invention provides a system for delivering a drug to a user, comprising a reservoir unit, a control unit, and at least one further reservoir unit or control unit, wherein each reservoir unit is adapted to receive at least one command from a control unit and perform an action in response thereto, and comprises a reservoir adapted to contain a liquid drug and includes, in a situation of use, associated outlet means. The system further comprises expelling means for expelling a drug out of the reservoir through the outlet means. Each control unit comprises control means providing one or more commands for controlling the operation of a reservoir unit, wherein each combination of a reservoir unit and a control unit is adapted to provide a system with different capabilities.

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority under 35 USC §119 of DanishApplication No. PA 2001 01403, filed Sep. 26, 2001 and U.S. ProvisionalApplication No. 60/327,117, filed Oct. 4, 2001; the contents of both arehereby incorporated by reference in their entirety.

BACKGROUND OF THE INVENTION

[0002] The invention relates to a modular drug delivery system,comprising a reservoir unit and a control unit in combination with atleast one further reservoir or control unit, whereby each combination ofa reservoir unit and a control unit provides different capabilities. Thesystem may be adapted for subcutaneous or intra-dermal infusion of aliquid formulation of an active ingredient such as insulin. The systemalso enables novel methods for treatment of diseases and conditions.

[0003] In the disclosure of the present invention reference is mostlymade to the treatment of diabetes by infusion of insulin, however, thisis only a preferred use of the present invention and other diseases andconditions may be treated with the present invention, which may be usedto deliver other medications in addition to or in place of insulin.

[0004] By treatment of certain medical conditions, such as insulintreatment of type 1 or 2 diabetes, either a conventional syringe can beused, or an injection device into which a cartridge containing the drugto be used is contained. The best known and mostly used injection devicefor this purpose is “pen”-formed devices typically used for treatment ofdiabetes types 1 or 2, where the pen can be considered a manuallyactuated pump serving as the infusion means for the cartridge.

[0005] A different class of devices is in the form of automatic infusionpump devices, also known as infusers, which are devices carried by andconnected to the user through a catheter or hypodermic needle. In itssimplest form the infuser will provide continuous delivery of the drugat a desired rate, however, more recent infusers can be programmed toinfuse the drug in accordance with any desired infusion profile, just asthe user manually can modify the infusion profile by, for example,adding bolus doses in relation to the meals.

[0006] The pump offers the possibility of good control of blood glucoseconcentration as it may simulate the course of the insulin production bya non-diabetic. However, the use of insulin pumps has been ratherlimited as the pumps have been expensive to manufacture as well ascomplex to operate. In an attempt to provide improved user friendliness,an early infuser used a cartridge similar to the ones used in the pendevices which meant that loading of the cartridge into the pumpmechanism was rather cumbersome just as the need to keep track of thebatteries not running flat added to the complexity experienced by theuser. However, later infusers have mostly been designed with reservoirswhich have to be filled by the user just prior to use.

[0007] Further, as more and more programming features were added, thiscomplexity alone made the infusers unsuitable for certain group ofusers.

[0008] Consequently, infusers were developed which tried to alleviatesome of these drawbacks. A first type of devices addressing theseproblems had in common the use of some kind of disposable “cassette”comprising some further means in addition to the mere reservoir, forexample the so-called “infusion set” comprising the means forintroducing the drug, e.g. an integrated or pre-connected catheterand/or infusion needle.

[0009] An early example can be found in WO 85/00523 teaching tointegrate the power source for the pump into a disposable unit, however,the disposable unit further comprises an infusion line for insertioninto a pump head to provide a peristaltic pump, this complicating themounting of the disposable unit.

[0010] The problem of mounting a cassette comprising an infusion linefor a peristaltic pump is addressed in FR-A-2 753 103 disclosing aninfusion system comprising a durable pump portion and a click-oncassette portion.

[0011] U.S. Pat. No. 4,886,499 discloses a portable device which in apreferred embodiment comprises a disposable unit which can be mounted ona reusable unit in a click-on fashion, the disposable unit comprisingthe drug containing reservoir as well as the pump, however, the batteryis arranged in the reusable unit.

[0012] By integrating even more disposable parts in a single disposablecassette unit the following generations of infusers were madeincreasingly simple to handle, yet providing improved functionality ofthe infuser per se. For example, U.S. Pat. No. 5,984,894 discloses aninfusion system comprising a durable unit forming a housing and adisposable unit containing the liquid reservoir and an energy reservoirfor energizing the pumping function together with all liquid-contactingelements of the device. The durable unit is in the form of a housingcomprising an inner space into which the disposable unit is adapted tobe inserted after which a lid is closed.

[0013] On the basis of the above-described two-unit system, U.S. Pat.No. 5,984,894 discloses that the mechanic and/or electronic interfacebetween the disposable and durable unit can be selected in accordancewith the actual circumstances. Accordingly, the durable unit maycomprise one or more of the elements: A controlling unit, a display,means for setting the controlling unit, a drive unit deliveringmechanical energy for driving the pump mechanism and a long lifeelectric cell energizing the controlling unit. The pumping mechanism maybe a complete low cost pump, e.g. a piezoelectric membrane pump, whichmay be disposed of after use. In other embodiments the pump mechanism isonly the unit comprising a pumping chamber and valves, and thismechanism is driven by an electric motor which is integrated in thedurable unit. When the controlling unit is energized by its own electriccell it is avoided that data stored in this unit are deleted during thechange of the disposable unit. It is possible to energize thecontrolling unit from the energy reservoir in the disposable unit sothat only during change the energizing is switched over to the long lifecell in the durable unit whereby this cell only acts as an emergencypower supply.

[0014] The disposable unit may comprise sensors measuring the pressurein the catheter directly in the outlet from the pumping mechanism. Thedisposable unit may further comprise a memory keeping an account of theamount of liquid left in the reservoir. By enclosing such a memory inthe disposable unit containing the liquid reservoir, this memory isfirmly connected to the reservoir. This is appropriate if the memoryshall be able to keep an account of the amount of liquid left in thereservoir. Data in the memory may be read out by the control unit andrepresented on the display.

[0015] The means for setting the controlling unit may comprise a socketwith electrical contacts, which socket is designed to receive andcommunicate with a plug having corresponding electric contacts andcarrying a programmed ROM-circuit defining the infusion data. The plugmay further carry a graphic representation of the infusion data storedin the ROM, i.e. how the infusion of a set 24-hours' dose is distributedover the 24 hours. This graphic representation may be marks on atransparent sheet so secured to the plug that it covers a watch dialdisplay when the plug is inserted in the socket, the marks indicatingperiods with increased or decreased infusion. By this construction theuser may avoid the relatively complicated programming of the pump as hemay plan the needed infusion profile or profiles in cooperation with hismedical adviser and thereafter he will only have to insert the plugwhich is in accordance with his immediate life style.

[0016] In an attempt to make the infusion device even simpler in use, anumber of fully disposable infusion devices has been proposed, see forexample U.S. Pat. No. 5,527,288 disclosing an intradermal drug deliverydevice which is entirely disposable and may be based either onmechanically or electronically controlled infusion means. Although thistype of device provides for improved convenience and safety of use, itwould normally be considered too costly to incorporate advancedfunctions such as flow measurement, display means or the ability tocooperate with a remote control unit. Addressing this problem, EP 1 177802 describes an infusion device comprising a disposable pump andreservoir unit with an attachable durable portion, the latter comprisingthe control means for the pump.

[0017] As follow from the above description of known devices, it isconsidered well known to “divide” an infusion device into a durable“control” unit and a disposable unit comprising a reservoir with aliquid to be infused, the actual mechanical, electrical and electronicinterface between the two units being the result of a normal designprocedure.

[0018] However, considering the infusion devices proposed during thelast two decades, it becomes apparent that these devices are based upon,literally, “dividing” existing infusers into a durable portioncomprising the more expensive components, and a disposable reservoirportion which is either inserted into a housing or attached to thedurable portion in a click-on fashion. In other words, the developmentsmade hitherto have entirely focused on the object of modifying existingconcepts in order to improve the functionality experienced by the user.

[0019] This said, the present inventors have realised that the aboveconcept of merely dividing what has hitherto been considered an infuserof a given type into a durable housing unit and a disposable cassetteunit has lead to a number of restrictions, which restrictions can bedivided into user-relevant restrictions and manufacturer-relevantrestrictions.

[0020] From the point of the user, when acquiring a delivery device(typically an infusion pump device), it has to be decided which “type”of infuser the user considers to be the most appropriate at the giventime. For example, a larger device comprising many features (e.g.programmability or a display) and which is adapted for largercartridges/cassettes containing a larger amount of drug, such a devicetypically being relatively heavy and constructed to be suspended by abelt. Examples of this type of infusing device are disclosed in U.S.Pat. No. 5,984,894 and FR-A-2 753 103. The user may also choose asmaller device which typically can be attached to the skin of the userby an adhesive, however, such infusion devices are normally rathersmall, with restricted capabilities in programmability. An example ofthis type of infusion device is disclosed in U.S. Pat. No. 4,886,499.

[0021] In this way the user is “locked” with an infusing device whichmay not be the most appropriate under all circumstances, for example,under normal day to day conditions the user may prefer a larger deviceproviding many user relevant features such as programmability, a displayas well as a large reservoir. However, during sports exercise or when itis desirable to hide the infuser under light clothing, the appropriateinfuser would be a small and simple device.

[0022] Indeed, it may be argued that it would be possible to attach asmaller reservoir unit to the larger type of infusion device, or toattach a larger reservoir unit to the smaller type of infusion device,however, this would hardly solve the problem as such infusion devicesmerely would be “a large infusion device with a small reservoirattached” or “a small infusion device with a large reservoir attached”;correspondingly, such infusion devices are not known in to the presentinventors.

[0023] It may also be argued that infusion devices today have come downin price such that it would be within economical reach for the averageuser to have the desired number of different devices which would make itpossible to just choose the type considered the most appropriate at agiven time and for a given need. However, in practise this approach isnot considered attractive by most users for a number of reasons, forexample, most users prefer to get accustomed with only one type ofinfusion device, just as swapping between a number of different deviceswould make it difficult to keep track of the amount of drug infused. Forthese reasons, in practise, most users choose to live with the type ofinfusion device considered the most appropriate for their average needs.

[0024] From the point of the manufacturer, the practise hitherto pursuedmeans that once it is decided to which “class” a given infusion devicebelongs, i.e. small or large, expensive or cheap, advanced or simple, itwill be difficult and/or expensive to adopt a given device to suit otherpurposes. For example, it would be almost impossible to modify a“large-type” infusion device comprising pump and control means adaptedfor longevity, for example as known from FR-A-2 753 103, to provide asmall and inexpensive device as known from U.S. Pat. No. 4,886,499.

[0025] Indeed, a given manufacturer may choose to develop two or moredifferent infusion devices each belonging to a given class of devices asdiscussed above, however, this approach has at least two drawbacks.Firstly, it will be expensive to both develop and keep a number ofsystems technologically updated, and secondly, the user may choosedifferent devices from different suppliers, this meaning loss ofbusiness as well as loss of brand loyalty.

SUMMARY OF THE INVENTION

[0026] Having regard to the above discussion of known infusion devices,the object of the present invention is to provide a concept for a drugdelivery device and system providing a high degree of flexibility forboth the user and manufacturer, allowing the user to modify the infusiondevice or system to better suit the given and changing circumstances,and allowing the manufacturer to provide this flexibility in a costeffective and efficient manner.

[0027] The present invention is based on the realisation that the “type”or “class” for a given drug delivery device or system advantageously canbe determined by an actual combination of units which allows a givennumber of inherently provided features (some or all) to be activated ormade accessible depending on which units of a system is actuallycombined. Correspondingly, the invention provides a modular drugdelivery system, comprising a reservoir and delivery unit and a controlunit in combination with at least one further reservoir or control unit,whereby each combination of a reservoir unit and a control providesdifferent capabilities.

[0028] More specifically, in a general aspect the present inventionprovides a system for delivering a drug to a user, comprising areservoir unit, a control unit, and at least one further reservoir unitor control unit, wherein each reservoir unit is adapted to receive atleast one command from a control unit and perform an action in responsethereto, and comprises a reservoir adapted to contain a liquid drug andincludes, in a situation of use, associated outlet means. The systemcomprises expelling means for expelling a drug out of the reservoirthrough the outlet means. Each control unit comprises control meansproviding one or more commands for controlling the operation of areservoir unit, wherein each combination of a reservoir unit and acontrol unit is adapted to provide a system with different capabilities.The term “capabilities” is used to denote a set of actions or functionsresulting from a combination of the two units. To provide the describedfunctionality, the reservoir unit comprises receiving means forreceiving the at least one command, and means for performing at leastone action.

[0029] As appears, a plurality of different systems may be providedcomprising different combinations of reservoir unit(s) and controlunit(s), a number of which will be described below.

[0030] In the context of the present application, a “command” providesor allows a given functionality, however, a command may typicallycomprise a series of signals providing a given action. For example, acommand for a given delivery rate would normally be in the form of aseries of signals actuating the expelling means thereby providing thedesired action, e.g. a series of membrane strokes resulting in a givenflow rate, or a series of signals controlling the contents of a display.Further, the nature of a command may be “active” such as whencontrolling a pump or a display, or “passive” when for exampleinformation is collected from a sensor element. Correspondingly, theterm “command” may be said to represent a given function.

[0031] Further, the concept of controlling the operation of the localprocessor means includes both “active” and “passive” control of thecommands. By active control is meant that a given command is activated,whereas passive control means that a given command is “allowed” to beexpressed. For example, in case a number of delivery rate commands isprovided, then a single command may be activated, whereas a command forcontrolling a display may always be “on”, alone the presence of adisplay in the control unit will “control” the command. Also, a controlprocessor may be used to control other elements than those controlled bya local processor, e.g. sensors.

[0032] The set of commands provided by the control means or the localprocessor means may comprise one or more commands controlling theexpelling means. In a simple configuration the “set” of commandscomprises a single command which would control the expelling means toexpel drug contained in the reservoir corresponding to a pre-determinedconstant delivery delivery rate, e.g. a basal rate, however, severalsuch commands providing different delivery rates or profiles may beprovided in combination with other commands. The expelling commands mayalso comprise one or more bolus commands by which a given volume of drugis infused over a shorter period of time. In addition to commandscontrolling the expelling means numerous other commands may be provided,e.g. display commands may control display means, memory commands maycontrol in- and output from memory means, sensor commands may controlsensor means, alarm commands may control alarm means, and transmissioncommands may control the transmission of data information.

[0033] In the context of the present application, the term “differentcapabilities” is used to indicate that the “potential” capabilities aredifferent, however, in case the capabilities are overlapping, the usermay choose to operate a given control unit corresponding to thecapabilities of another control unit, or two different advanced unitsmay be used in the same way. For example, a control unit allowinguser-programming of infusion profiles as well as a bolus function may beused to activate a simple constant flow rate corresponding to thecapabilities of a simple control unit. This means that seen from thereservoir unit there will be no difference between the two controlunits.

[0034] In an exemplary embodiment, the reservoir unit comprises localreceiving means cooperating with local processor means for receivingcontrol commands from at least one control unit, where at least one ofthe control units comprises control processor means, and controltransmission means cooperating with the control processor means fortransmitting control commands to the local receiving means forcontrolling a combination of commands. Advantageously, the reservoirunit comprises local transmission means cooperating with the localprocessor means for transmitting data information to control receivingmeans in at least one control unit, where at least one of the controlunits comprises control receiving means cooperating with controlprocessor means for receiving data information from the local processor.The data information may be flow related (e.g. the amount of druginfused or left in the reservoir) or may originate from a sensorincorporated in the reservoir unit, e.g. a blood glucose sensor.

[0035] By providing a control processor the flexibility of the system isenhanced, e.g. by means of the control processor an advanced interfacebetween the user and the available control commands can be establishedjust as received data information can be stored, processed and used togenerate new control commands.

[0036] In exemplary embodiments at least one transmission means and thecorresponding receiving means are adapted for wireless transmission ofcommands or data information, this allowing the control unit to be usedas a remote control. In case two-way transmission is provided for acombination of two units, both way may function wirelessly. However, fora given reservoir unit control units may be provided which are adaptedfor wireless transmission in one direction only but not necessarily thesame. Transmission may be based on any suitable technology such as RF,IR or induction.

[0037] In an exemplary embodiment, the reservoir unit and at least onecontrol unit comprise mating coupling means so as to allow the controlunit to be secured to the disposable unit, the mating coupling meansincluding communication means allowing information to be transferred,e.g. control commands and data information. The mating coupling meansmay include communication means comprising one or more of: electricalcontacts means, opto-electrical means, wireless transmission means, ormechanical contact means allowing information to be transferred.

[0038] The mating coupling means may be adapted for releasably securinga control unit to a reservoir unit so as to allow the control unit to bereadily removed and replaced when desired, or the mating coupling meansmay be adapted for permanently securing the control unit to thedisposable unit.

[0039] In case all transmission of commands and data are performed bywireless means, the reservoir unit is advantageously provided as asealed unit adapted to resist water to a given degree, e.g. beingsuitable for being taken into the shower or for going swimming.

[0040] The control or reservoir unit may be provided with more than onetype of communication means, this allowing a given unit to communicatewith different types of other units or to communicate with the same unitin different ways. The above-described “advanced” communication meansmay also be combined with means allowing for mechanical communication aswill be described below. For example, a reservoir unit may be providedwith first means which allows a simple mechanical control unit to startthe infusion process, as well as second means allowing high-levelbidirectional communication between the two units, either the samecontrol unit or a different unit. A given control unit adapted forwireless communication may also be configured to be matingly attached tothe reservoir unit in which case communication may still rely onwireless means or may be fully or partly replaced by contact means justas additional contact means by be used for transmission of additionalcommands or data.

[0041] In an exemplary embodiment at least one control unit comprises anattachable subunit and a remote subunit, the subunits comprisingtransmission means and corresponding receiving means adapted forwireless transmission of commands or data information to and/or from therespective unit(s). The reservoir unit and the attachable subunitcomprise mating coupling means allowing the attachable subunit to besecured to the reservoir unit, the mating coupling means includingcommunication means allowing commands or data information to betransferred, whereby commands or data information to and/or from thereservoir unit can be transmitted wireless between the remote subunitand the reservoir unit. By this configuration, the additional costsassociated with the provision of wireless communication between thereservoir and a control unit can be transferred from the reservoir unit(which may be a prefilled disposable unit) to the durable control unit.A replaceable energy source may be provided in the attachable subunitfor either energizing the delivery means in the reservoir unit ordriving mechanical command means arranged in the attachable subunit.Indeed, for such a configuration the user will have to switch theattachable subunit each time the reservoir unit is changed, for whichreason the assembled pump unit may be categorized as a semi-disposablesystem.

[0042] The energy source for driving the expelling means and the localprocessor may be supplied by a battery incorporated in the (disposable)reservoir unit, however, for environmental reasons the battery may beprovided as a “reusable” unit which will have to be switched each timethe reservoir unit is changed. In case a control unit is used which isfully or partly (e.g. as described above) attached to the reservoir unitduring operation, energy may be supplied from this unit.

[0043] The outlet means associated with the reservoir may be in directfluid communication with the reservoir (e.g. in case the expelling meansis arranged “before” the reservoir as for a piston pump) or indirectfluid communication (e.g. in case the expelling means is arranged“after” the reservoir as for a membrane pump). The outlet means may beadapted to be brought in fluid communication with infusion means (e.g. acatheter tubing or transcutaneous access means such as an infusionneedle, a flexible infusion cannula or a plurality of micro-penetrators)or may comprise these. In the latter case the fluid communication may beestablished just prior to use, before or after the drug delivery devicehas been arranged on the user.

[0044] The delivery device may comprise outlet means being adapted tocooperate with or comprising infusion means. The infusion means may bein the form of a catheter tubing or transcutaneous access means such asan infusion needle, a flexible infusion cannula or a plurality ofmicro-penetrators. In exemplary embodiments the reservoir is aprefilled, flexible reservoir.

[0045] Display means may be provided on any of the units or subunitscomprising a processor capable of driving a display, however, for costreasons a display may be included only in a control unit or,alternatively, in one or both of its subunits. The display means may beused for displaying the contents of memory and/or setting meanscomprised in the delivery system.

[0046] A control may be provided with additional input and output meansallowing it to communicate with external computer- and/or expertsystems, just as the remote may be used in combination with a closedloop system comprising a blood glucose sensor.

[0047] In a first specific aspect the present invention provides asystem for delivering a drug to a user, comprising a reservoir unit andat least first and second control units.

[0048] In an exemplary embodiment the reservoir unit comprises areservoir adapted to contain a liquid drug and comprising, in asituation of use, associated outlet means, expelling means for expellinga drug out of the reservoir through the outlet means, and localprocessor means providing a number of commands. One or more of thecontrol unit comprises control means for controlling the operation ofthe local processor means, wherein each control unit is adapted tocontrol a different command or combination of commands, therebyproviding each combination of the disposable unit and a control unitwith different capabilities. In this way the reservoir unit is providedas a unitary unit comprising both a reservoir and the expelling means.

[0049] In the context of the present invention, the term “capability”denotes an “activity”, e.g. different reservoir units merely comprisingdifferent amounts or types of drug would not possess differentcapabilities.

[0050] In a further exemplary embodiment the reservoir unit comprises areservoir adapted to contain a liquid drug and comprising, in asituation of use, associated outlet means, the reservoir unit beingadapted to receive at least one command from a control unit and performan action in response thereto, the system comprising expelling means forexpelling a drug out of the reservoir through the outlet means. Eachcontrol unit comprises control means providing one or more commands, inexemplary embodiments including at least one command controlling theexpelling means, wherein each control unit is adapted to provide adifferent command or combination of commands, thereby providing eachcombination of the disposable unit and a control unit with differentcapabilities. The reservoir unit may comprise local processor means andat least one electronically controllable element associated with thelocal processor means, the local processor means being controllable byat least one control unit.

[0051] As appears, in contrast to the first described embodiment, thefunctionality of the reservoir unit may be fully controlled by thecontrol unit, the reservoir unit merely providing actuatable means (e.g.expelling means such as a pump) controllable by commands from thecontrol unit. In this context a “command” provides a given functionalityand may be of either electrical or mechanical nature. For example, thereservoir unit may comprise a membrane pump being controlled directly bythe control unit (i.e. the individual pump strokes), or the reservoirunit may comprise a pump of the constant flow-rate type (e.g. a bleedinghole pump) which is mechanically controlled by flow control meansprovided in the control unit. For example, in a very simpleconfiguration, a bleeding hole pump comprises two different flowrestrictors one of which is activated by a mechanical command when acorresponding control unit is locked in place. In this way a fullymechanical system may be provided comprising e.g. a spring driven pumpand two mechanical control units by which one of two flow rates isselected when the corresponding control unit is attached.

[0052] The expelling means may be comprised in either the reservoirunit, the control unit or divided between the two units. In exemplaryembodiments, the expelling means is fully comprised in the reservoirunit which is provided as a unitary unit. Depending on the nature of theexpelling means, the expelling means per se may be fully comprised inthe reservoir unit but with an interface controlled dynamically by thecontrol unit. For example, a bleeding hole pump may be activated by amechanical “on” command which opens for the flow of drug, andsubsequently controlled by a “flow rate” command in which a flow conduitis opened and closed by means arranged in the control unit.

[0053] In exemplary embodiments, the expelling means is controlled by acontrol unit providing at least one command controlling the expellingmeans, the control unit being adapted to control at least one commandcontrolling the expelling means (either directly or via local processormeans), however, the expelling means may be controlled independently ofthe control unit.

[0054] For example, a reservoir unit may be adapted to provide a givendelivery rate without the cooperation of a control unit, the deliverymeans being either “self-controlled” (e.g. a spring-driven bleeding holepump or an osmotic pump) or electronically controlled by local processormeans (e.g. a membrane or piston pump). In this configuration thecontrol units merely provide additional functions by controllingadditional commands or actions, e.g. transmission commands, displaycommands, memory commands etc.

[0055] In a second specific aspect the present invention provides asystem for delivering a drug to a user, comprising at least first andsecond reservoir units and a control unit.

[0056] In an exemplary embodiment at least the first and secondreservoir units each comprises a reservoir adapted to contain a liquiddrug and comprising, in a situation of use, associated outlet means,expelling means for expelling a drug out of the reservoir through theoutlet means, and local processor means providing one or more commands,wherein each reservoir unit provides a different combination ofcommands. The control unit comprises control means for controlling theoperation of the local processor means, wherein the control means isadapted to control, at least partially, the different combinations ofcommands, thereby providing each combination of a reservoir unit and thecontrol unit with different capabilities.

[0057] In a further exemplary embodiment each reservoir unit comprises areservoir adapted to contain a liquid drug and comprising, in asituation of use, associated outlet means, each reservoir unit beingadapted to receive at least one command from the control unit andperform an action in response thereto, the system comprising expellingmeans for expelling a drug out of the reservoir through the outletmeans. The control unit comprises control means providing a number ofcommands, in exemplary embodiments including at least one commandcontrolling the expelling means, whereby each combination of adisposable unit and the control unit is provided with differentcapabilities.

[0058] In a third specific aspect the present invention provides asystem for delivering a drug to a user, comprising at least first andsecond reservoir units and at least first and second control units.

[0059] In an exemplary embodiment at least the first and secondreservoir units each comprises a reservoir adapted to contain a liquiddrug and comprising, in a situation of use, associated outlet means,expelling means for expelling a drug out of the reservoir through theoutlet means, local processor means providing one or more commands,wherein each reservoir unit provides a different combination ofcommands. At least the first and second reservoir units each comprisescontrol means for controlling the operation of a local processor means,wherein the control means is adapted to control different commands or,at least partially, different combinations of commands, therebyproviding each combination of a reservoir unit and a control unit withdifferent capabilities.

[0060] In a further exemplary embodiment each reservoir unit comprises areservoir adapted to contain a liquid drug and comprising, in asituation of use, associated outlet means, each reservoir unit beingadapted to receive at least one command from the control unit andperform an action in response thereto, the system comprising expellingmeans for expelling a drug out of the reservoir through the outletmeans. Each control unit comprises control means providing one or morecommands, wherein each control unit is adapted to provide a differentcommand or combination of commands, thereby providing each combinationof a reservoir unit and a control unit with different capabilities.

[0061] As for the first specific aspect, the expelling means of thesecond and third aspect may be controlled by the control unit or becontrolled independently of the control unit. Correspondingly, itreadily appears that any of the features described for a reservoir orcontrol unit in respect of the general aspect can be utilized withcorresponding effect for systems comprising different combinations ofunits as defined for the first, second and third aspects of the presentinvention.

[0062] In the above disclosure of the invention, the components of thesystem have been described primarily with respect to technical features.In the following different exemplary “useroriented” configurations willbe disclosed.

[0063] In one aspect, the “external” configuration of the presentinvention may be based on the concept of a reservoir unit (e.g. adisposable, prefilled unit) defining the outer boundaries, or theplatform, for the system to which different control units (e.g. durableunits) can be attached, the different control units providing combineddevices with different capabilities, this in contrast to most of theknown systems which are based on the concept of the durable unitdefining, in general, the platform and the outer boundaries for thecombined infusion system, the disposable reservoir unit being insertedor attached to this platform.

[0064] When the control unit is attached to the reservoir duringoperation, the resulting drug delivery device may be considered a“combined” device comprising a reservoir unit and a control unit.

[0065] The combined device comprises expelling means (e.g. a pump) forexpelling a liquid from the reservoir, however, according to thespecific design thereof, the expelling means may be comprised eitherentirely in the reservoir unit or it may be made up of aliquid-contacting portion comprised in the reservoir unit and adapted tocooperate with expelling means comprised in the control unit.

[0066] The control unit may be attached in any desirable way. In anexemplary configuration the control unit is inserted into an opening orrecess of the reservoir unit adapted to accommodate and connect to thecontrol unit, the units comprising corresponding mating coupling means.For such a configuration the reservoir unit could be said to represent ahousing into which the control unit is inserted fully or partly, i.e.either flush with a surface of the disposable unit or protruding more orless. In another exemplary embodiment the control unit is in the form ofa member which can be attached onto the housing of the disposable unit,for example along an edge thereof. In case the control unit is in theform of remote control unit, the units may be adapted to be attached toeach other in the same way when it is desirable to have only one unit.

[0067] In an exemplary embodiment the reservoir unit comprises a housinghaving a first surface configured to be arranged against the skinsurface of a user, and a second surface facing away from the firstsurface and comprising means for allowing a control unit to be attachedin a mating relationship. In an exemplary embodiment the first surfaceis provided with an adhesive means for attaching the housing to the skinof the user, the second surface preferably being arranged substantiallyopposite the first surface.

[0068] As discussed above, the actual mechanical, electrical andelectronic interface between the two units is decided during a normaldesign procedure, however, the interface should designed in such a way,that the highest degree of constructional freedom is provided for bothof the units, allowing the “controlling capabilities” of the controlunit to be varied from very complex versions to very simple versions.

[0069] More specifically, the control unit may comprise control meansadapted primarily to provide a user interface allowing the user to“communicate” with the infusion device, e.g. providing the user withinformation of the present settings, the amount of previously infuseddrug for a given period, the type of drug in the actual disposable unitand the amount remaining, as well as allowing the user to program orchange the actual settings. The control unit may comprise an energysource for providing the control means with electric energy, thisallowing the control unit to be operated when disconnected from thereservoir unit as well as providing energy for supporting any volatileinformation stored in the control unit (e.g. individual settings andinformation of infusion history), however, energy for operating thecontrol unit when attached to the reservoir unit may be provided from anenergy source within the latter.

[0070] The interface between the control and the reservoir unit isadvantageously designed for communication between different “types” ofmeans for a given functionality such that a general set of controlcommands (e.g. for a given infusion rate) can be used to control adiversity of expelling means having diverse nature. In the same way,different types of reservoir units may communicate with the controlmeans also using a general set of commands informing the control meansabout the type of disposable unit, the amount remaining the reservoiretc.

[0071] The communication between the control unit and the reservoir unitmay take place by any suitable means, including electrical contacts,opto-electrical means (e.g. IR light) or RF radio-transmission. Thecontrol or the reservoir unit may be provided with more than one type ofcommunication means, this allowing a given unit to communicate withdifferent types of other units. The above-described “advanced”communication means may also be combined with means allowing formechanical communication as will be described in greater detail below.For example, a reservoir unit may be provided with first means whichallows a simple mechanical control unit to start the infusion process,as well as second means allowing high-level bi-directional communicationbetween the two units.

[0072] In the above, relatively complex control units have beendescribed having advanced control or display features which in mostcases require the provision of electronic means to be implemented.However, it is also within the scope of the present invention to providemuch simpler control units based for example on “mechanicalcommunication” between the control unit and the reservoir unit. In avery simple form the control unit functions merely as an “onbutton” whenattached, or as an “on-off” switch in case the control unit isdetachable. Such a simple control unit may further comprise meansallowing the disposable unit to be “programmed” (i.e. activating a givenset of commands) depending on the configuration of the control unit. Forexample, the reservoir unit may be configured to provide a plurality ofdifferent basal rates, the actual basal rate being set by theconfiguration of the control unit. For this kind of control differentcontrol units may be provided for each basal rate or a single controlunit may be set in accordance with the desired rate (e.g. in accordancewith the orientation when attached). In exemplary embodiments of theabove-described simple versions of the control unit, the communicationbetween the control unit and the reservoir unit is based on mechanicalinteractions, whereby the mechanical configuration of the control unitis detected by the reservoir unit. The mechanical control means maycooperate with any suitable kind of contact means in the reservoir unit,e.g. electrical contacts or opto-electrical means.

[0073] Although the above-described exemplary embodiments provide alarge degree of constructional freedom, it is also within the scope ofthe present invention to provide cooperating units which to a higherdegree is adapted specifically to each other. For example, the controlunit may comprise pump means in the form of a peristaltic pump whichwill only operate in combination with a reservoir unit comprisingexpelling means in the form of a corresponding tubing, or a drive meansadapted to operate a valve-controlled expelling pump associated with thereservoir.

[0074] In the above description of the invention the terms “disposable”and “durable” have been used, the latter traditionally defining the partof the system which as a consequence of a relatively high price isintended for being used for a longer period, normally several years.Typically, the high price was due to the cost of a relatively expensivehousing as well as pump and control means, the latter includingprogramming means. However, strictly speaking, any “durable” unitcomprising the above components may be considered a disposable unit incase the cost thereof is sufficiently low. In the same way, the“disposable” unit may be semi-disposable such that the reservoir can bere-filled with a given drug.

[0075] By (also) providing a disposable control unit a number ofadvantages is achieved from the sight of the manufacturer as well byallowing a large number of variants to be produced and distributed in aneffective manner. For example, different versions of the reservoir unitas well as different versions of the control unit may be produced atdifferent locations and shipped independently of each other to a givenlocation, where the units may be assembled, for example at the point ofsale. In this way cheap or expensive versions of the two units may becombined as desired. When the control unit is sold as a disposablecomponent, the mating coupling means may be adapted to permanentlysecure the control unit to the housing preventing the reuse of thecontrol unit. Actuating the system to start drug delivery may be byfurther manipulation of the control unit (e.g. pressing or turning) orby additional means provided on the reservoir unit. In this way it wouldbe possible to produce one or more control units which just prior toinstallation are given a functionality corresponding to either a cheapor a more expensive version.

[0076] In exemplary embodiments, the coupling means provided in thereservoir unit is of a “general” type allowing different control modulesto be locked in either a permanent or a releasable manner in accordancewith the type of control module.

[0077] The expelling means may be of any desirable nature, such as knownfrom U.S. Pat. Nos. 4,340,048 and 4,552,561 (based on osmotic pumps),U.S. Pat. No. 5,858,001 (based on a piston pump), U.S. Pat. No.6,280,148 (based on a membrane pump), U.S. Pat. No. 5,957,895 (based ona flow restrictor pump (also know as a bleeding hole pump)), or U.S.Pat. No. 5,527,288 (based on a gas generating pum p), which all in thelast decades have been proposed for use in inexpensive, primarilydisposable drug infusion pumps; the cited documents being incorporatedby reference.

[0078] The outlet means associated with the reservoir may be in directfluid communication with the reservoir (e.g. in case the expelling meansis arranged “before” the reservoir as for a piston pump) or indirectfluid communication (e.g. in case the expelling means is arranged“after” the reservoir as for a membrane pump). The outlet means may beadapted to be brought in fluid communication with infusion means (e.g. acatheter tubing or transcutaneous access means such as an infusionneedle, a flexible infusion cannula or a plurality of micro-penetrators)or may comprise these. In the latter case the fluid communication may beestablished just prior to use, before or after the drug delivery devicehas been arranged on the user.

[0079] The reservoir may be prefilled with the liquid to be infused andthus ready to be used, or it may be adapted to be filled with the liquidfrom an external source prior to use, the latter in case a prefilledreservoir will result in reduced shelf-life for the contained liquid.

[0080] As used herein, the term “drug” is meant to encompass anydrug-containing flowable medicine capable of being passed through adelivery means such as a hollow needle in a controlled manner, such as aliquid, solution, gel or fine suspension. Representative drugs includepharmaceuticals such as peptides, proteins, and hormones, biologicallyderived or active agents, hormonal and gene based agents, nutritionalformulas and other substances in both solid (dispensed) or liquid form.In the description of the exemplary embodiments reference will be madeto the use of insulin. Correspondingly, the term “subcutaneous” infusionis meant to encompass any method of parenteral delivery to a subject.

BRIEF DESCRIPTION OF THE DRAWINGS

[0081] In the following the invention will be further described withreferences to the drawings, wherein

[0082]FIG. 1A is a schematic representation of a first embodiment of theinvention,

[0083]FIG. 1B is a schematic representation of a further embodiment ofthe invention,

[0084] FIGS. 2A-2B show a second embodiment of the invention,

[0085] FIGS. 3A-3B show a third embodiment of the invention,

[0086] FIGS. 4A-4B show a fourth embodiment of the invention,

[0087]FIG. 5 shows a fifth embodiment of the invention,

[0088]FIG. 6 shows a sixth embodiment of the invention, and

[0089] FIGS. 7A-7C show different combinations of a reservoir unit and acontrol unit.

[0090] In the figures like numerals are used to denote like or similarstructures.

DETAILED DESCRIPTION OF THE INVENTION

[0091]FIG. 1A shows a schematic representation of a first embodiment ofthe invention. Correspondingly, the configuration of the differentstructures as well as there relative dimensions and locations areintended to serve illustrative purposes only.

[0092] More specifically, a drug delivery system (here: infusion system)1B comprises a reservoir unit 10 in combination with three differentcontrol units 20, 30, 40, in which a combination of the reservoir unitand one of the control units provides an operative drug delivery device.

[0093] The reservoir unit comprises a drug reservoir 11 and a pump 12comprising an outlet means 13 and adapted for infusing a drug into abody of a user in accordance with instructions (i.e. a local command)received from a local processor 15. The pump may be of the meteringtype, i.e. the amount of drug infused corresponds to the controllingsignals received from the local processor or the infusion unit may beprovided with detecting means for determining the amount of drugactually infused (not shown). The local processor is associated with alocal receiving means 16 cooperating with the local processor means forreceiving control commands from at least one of the control units. Anenergy source 19 is provided in the form of a battery.

[0094] The three control units are in the form of a basic unit 20, astandard unit 30 and an advanced unit 40. The standard control unitcomprises a control processor 35 associated with a transmitter 36 forwireless transmitting control commands to the local processor via thelocal receiving means. The control unit further comprises a display 31associated with the control processor. The display may be used when theuser enters information into the control unit via user-accessible inputmeans (not shown), e.g. the desired size for a bolus command or programdata changing the infusion rate or profile, the information beingtransferred via the transmitting means. An energy source 39 is providedin the form of a battery. The standard control unit 30 may be attachedto the reservoir unit 10 by releasable means 14, 34.

[0095] The first combination is based on one-way transmission ofcommands from the control unit to the reservoir unit, however, thereservoir unit comprises local transmission means 17 cooperating withthe local processor means for transmitting data information to controlreceiving means 47 provided in the advanced control unit 40. The datamay comprise information as to the initial amount of drug in thereservoir, the current amount of drug in the reservoir, the infusionrate, information from a sensor element or ID information identifyingthe given reservoir unit. The advanced control unit further comprisesmemory means 42 allowing transmitted and/or received commands/data to bestored and recalled. The memory means may be detachable, e.g. in theform of a memory stick or card.

[0096] The first and second combinations are based on one-waytransmission of commands from the control unit to the reservoir unit,however, the reservoir unit further comprises second local receivingmeans 18 adapted to cooperate mechanical command means 28 provided onthe basic control unit 20. More specifically, the basic control unit isprovided with a protrusion 28 adapted to be received in the second localreceiving means when the reservoir unit and the control unit areattached to each other by releasable or non-releasable means 14, 24. Thereservoir unit may be adapted to provide a single basal infusion ratewhen combined with the basic control unit, or it may be adapted toprovide a plurality of infusion rates which can be specificallyactivated by mechanical commands from a corresponding number ofdifferent basic control units.

[0097]FIG. 1B shows a schematic representation of a further embodimentof the invention. Correspondingly, the configuration of the differentstructures as well as there relative dimensions and locations areintended to serve illustrative purposes only.

[0098] More specifically, a drug delivery system 1B comprises twodifferent reservoir units 110, 150 in combination with a control unit120 in which a combination one of the reservoir units and the controlunits provides an operative drug delivery device.

[0099] In contrast to the control units of the first embodiment, thecontrol unit 120 comprises an attachable subunit 130 and a remotesubunit 140, the subunits comprising transmission means andcorresponding receiving means adapted for wireless transmission ofcommands or data information to and/or from the respective unit(s). Forthis reason the control unit 120 may be considered a control assembly.The reservoir units of the system and the attachable subunit comprisemating coupling means allowing the attachable subunit to be secured to areservoir unit, the mating coupling means including communication means131, 132 allowing commands or data information to be transferred,whereby commands or data information to and/or from a reservoir unit canbe transmitted wireless between the remote subunit and the reservoirunit via the attachable subunit.

[0100] The remote subunit 140 generally corresponds to the advancedcontrol unit of the first embodiment, i.e. comprising a controlprocessor 145 associated with transmitting and receiving means 146, 147,a display 141 associated with the control processor, memory means 142and an energy source 149. The attachable subunit also comprises aprocessor 135 associated with receiving means and transmitting means136, 137 and an energy source 139. In the shown embodiment theattachable subunit further comprises a mechanical pump actuator 131serving as a mechanical means for transmitting commands to acorresponding pump in a reservoir unit, as well as electrical contactmeans 132 for receiving information from a reservoir unit, i.e.providing “passive” control commands allowing the sensor to be used. Thereservoir unit and the attachable subunit are attached to each other byreleasable means associated with the mating coupling means.

[0101] The first reservoir unit 110 comprises a drug reservoir 111 and apump 112 comprising an outlet means 113 and adapted for infusing a druginto a body of a user in accordance with commands received from theattachable subunit, as well as a sensor 114 in communication withelectrical contact means 115 for transmitting information to theattachable subunit, the electrical contact means also providing theenergy necessary for driving the sensor. The pump comprises a mechanicalinterface allowing the pump to be driven in a controlled manner via thecommand/actuator means 131. In the shown embodiment the pump is in theform of a membrane pump driven by command actuators located in theattachable subunit, however, a variety of pump and command means may beutilized. For example, the pump may be of the bleeding hole typecomprising valve means controlled by the control unit (preferably incombination with flow control means) or may essentially correspond tothe above-described first embodiment in which the reservoir unitcomprises a local processor which in this further embodiment would becontrolled via the processor 135 and energized from the battery 139. Thesensor 114 is adapted for detecting a condition in the body of the usersuch as the blood glucose level. The detected glucose level may betransmitted to the remote subunit and displayed on the display or it maybe utilized for controlling the delivery of the drug in response theretoin a closed loop arrangement.

[0102] Whereas a combination of the first reservoir unit and the controlunit provides an advanced pump assembly based on two-way transmission ofcommands/data between the control unit and the reservoir unit andcomprising an integrated sensor system, the second reservoir unit 150 isa basic unit merely providing a controllable pump 152 in combinationwith a drug reservoir 151.

[0103]FIGS. 2A and 2B show a second embodiment of the invention. Morespecifically, a drug delivery (here: infusion) system 2 comprises areservoir unit 200 in combination with two different control units 250,260, in which a combination of the reservoir unit and one of the controlunits provides an operative drug delivery device.

[0104] The reservoir unit comprises an outer housing defining the outerboundaries for the combined infusion device, the housing having an uppersurface 201, a rim portion 202 and a lower surface 203 adapted to bearranged towards a skin surface of a user. Preferably the lower surfaceis provided with an adhesive (not shown) allowing the device to beattached directly to the skin surface. In the upper surface an opening204 is provided adapted to receive a control unit, the reservoir unitand the control units including mating coupling means 205, 255, 265 soas to allow a control unit to be secured to the reservoir unit, themating coupling means including electrical contacts 206, 256, 266.

[0105] The control unit 250 comprises a housing having an upper surface251, a rim portion 252 and a lower surface 253, the control unit beingadapted to be received in a corresponding opening in the reservoir unit200, the control unit including mating coupling means 255 so as to allowthe control unit to be secured to the disposable unit. It is to be notedthat the coupling means shown on the control units respectively thereservoir unit are not intended to engage each other but are merelyarranged for illustrative purposes. In accordance with the actual designof the units, the electrical contacts may provide command/data transferto and/or from the control unit as well as providing the control unitwith energy from an energy source provided in the disposable unit orvice versa.

[0106] The control unit 250 comprises a user interface having a useractuatable key 257 and a display 258. In the shown embodiment only asingle key is provided, for example in the form of an on-off switch or abolus key. In accordance with the actual design of the control unit, thedisplay may provide the user with different kinds of information, e.g.the actual infusion profile, the amount of drug infused (e.g. forinsulin a number of units) for a given period, the amount of drugremaining in the disposable unit etc.

[0107] As the basal infusion rate for any drug to be infused using thedevice of the invention will be dependent of the individual user, itcould be possible to set such a basal rate using control means arrangedon either of the two units. As this setting normally will not have to bechanged on a regular basis, these control means may be provided onportions of the units which are hidden to the user when the two unitsare secured to each other, for example on the rear surface of thecontrol module.

[0108] The second control unit 260 essentially corresponds to the firstcontrol unit 250, the differences being a group of user actuatable keys267, e.g. allowing the unit to be program med by the user, as well asanother display 268, e.g. having graphic and/or alpha-numericcapabilities. The second control unit further comprises a memory meansas well as a back-up energy source therefore (not shown). In the shownembodiment all pump components in contact with the drug is contained inthe disposable part, however, according to the actual type of pump, somecomponents thereof may be provided in the control unit, for example asmall electric motor actuating a valve pump comprised in the disposableunit. The memory means allows the control unit to be released from afirst disposable unit and placed in a second disposable unit withoutloss of information contained in the control unit, e.g. specific programsettings or information regarding the amount of drug infused for one ormore periods.

[0109] In a further embodiment (not shown), the disposable unit maycomprise additional means providing a back-up memory function for thecontrol unit, this allowing a new or pre-used control unit to be updatedwhen inserted into such a disposable unit.

[0110]FIG. 2B shows the reservoir unit 200 with the control unit 250mounted. As can be seen, the control unit is fully embedded in theopening of the reservoir unit, the upper surfaces of the two units beingarranged flush with each other. Advantageously, such a design could beused in cases where the combined device is sold as a disposable singleunit (preferably with a basic control unit as described above), thecontrol unit being inserted into the opening before being sold. Indeed,the shown flush configuration may also be used for control unitsintended for re-use.

[0111] Not to be seen, the reservoir unit comprises a reservoir, a pumpmeans for pumping drug contained in the reservoir to an outlet opening(not shown) and an energy source for operating the pump and, if deemedappropriate, the control unit when attached. As described above withreference to the second control unit 260, the pump means may serve fullyor only partly as an operating pump, the remaining components beingprovided by the control unit. Further, depending on the actual type anddesign of the pump, control means for operating the pump may be providedin either of the units or divided therebetween as discussed in greaterdetail in the introductory portion.

[0112]FIGS. 3A and 3B show a third embodiment of the invention. Morespecifically, a drug delivery (here: infusion) system 3 comprises areservoir unit 300 in combination with three different control units350, 360, 370 in which a combination of the reservoir unit and one ofthe control units provides an operative drug delivery device.

[0113] The reservoir unit comprises an outer housing defining the outerboundaries for the combined infusion device, the housing having an uppersurface 301, a rim portion 302 and a lower surface 303 adapted to bearranged towards a skin surface of a user and preferably being providedwith an adhesive. The reservoir unit is provided with a “cut-out”portion 304 adapted to receive a control unit, the reservoir unit andthe control units including mating coupling means 305, 355, 365, 375 soas to allow the control unit to be secured to the reservoir unit, themating coupling means including electrical contacts. As can be seen, thelower portion comprises an extension in the form of a base plate portionwhich extends in a tongue-like fashion corresponding to the cut-outportion of the housing, the upper surface 307 of the base plate portionand the portion 312 of the rim facing towards the base plate portionproviding mounting surfaces for a control unit and together defining aconfinement for a control unit. As appears from the figure, theconfinement 304 is provided within the outer boundaries of thedisposable housing. The reservoir unit 300 comprises the same internalcomponents as described for the second embodiment.

[0114] The control unit 350 comprises a housing having an upper surface351, a rim 352 and a lower surface 353, the rim comprising a connectingportion 354. The control unit is adapted to be received in thecorresponding confinement 304 in the reservoir unit 300, the controlunit including mating coupling means 355 on the connecting portion 354and the lower surface (not shown) so as to allow the control unit to besecured to the corresponding portions 312, 307 of the reservoir unit,the mating coupling means including electrical contacts. The couplingmeans may be of the same type as discussed above with reference to theFIG. 2A embodiment.

[0115] The control unit 350 comprises a simple user interface having asingle user actuatable key 357, for example in the form of an on-off keyor a bolus key, but no display.

[0116] The second control unit 360 has the same dimensions as the firstcontrol unit 350, but comprising two keys and a display 368. The displaymay provide the user with information as to infusion settings and/orhistory, just as the display would allow the control unit to bemenu-programmable using the two keys. The third control unit is somewhatlarger (and thus larger than the upper base plate surface 307) andcomprises four keys and a larger display 378.

[0117]FIG. 3B shows the reservoir unit 300 with the control unit 350mounted. As can be seen, the control unit fully occupy the confinement304 defined within the outer boundaries of the disposable housing, theupper and outer rim surfaces of the two units being arranged flush witheach other. The control unit may be attached in releasable or anon-releasable m anner.

[0118]FIGS. 4A and 4B show a fourth embodiment of the invention. Morespecifically, a drug delivery system 4 comprises two reservoir units400, 410 in combination with a control unit 450 in which a combinationof one of the reservoir units and the control unit provides an operativedrug delivery device. The first reservoir unit 400 has the same generalouter configuration as in the second embodiment comprising an opening404 adapted to receive a control unit, whereas the second reservoir unit410 has the same general outer configuration as in the third embodimentcomprising a cut-out portion 414 adapted to receive a control unit. FIG.4B shows the reservoir unit 410 with the control unit 450 mounted.

[0119]FIG. 5 shows a fifth embodiment of the invention in which a drugdelivery system 5 comprises two reservoir units 500, 510 in combinationwith an advanced control unit 550 having a keyboard and a display,whereby a combination of one of the reservoir units and the control unitprovides an operative drug delivery device. In contrast to theembodiments described with reference to FIGS. 2-4, the units comprisewireless communication means 506, 516, 556 for transmission ofcommands/data and the units are not adapted to be connected to eachother. The first reservoir unit 500 may represent a basic reservoir unitproviding e.g. a single basal rate which can be activated by the controlunit. The second reservoir unit 510 may represent an advanced reservoirunit being fully programmable by means of the control unit (e.g.allowing the user to enter a desired infusion rate or profile or a boluscommand) as well as providing two-way exchange of command instructionsand data information.

[0120]FIG. 6 shows a sixth embodiment of the invention in which a drugdelivery system 6 comprises two control units 650, 660 in combinationwith an advanced reservoir unit 600 whereby a combination of one of thecontrol units and the reservoir unit provides an operative drug deliverydevice. In contrast to the embodiments described with reference to FIGS.2-4, the units comprise wireless communication means 606, 556, 566 fortransmission of commands/data and the units are not adapted to beconnected to each other.

[0121] The first control unit 650 comprises a simple user interfacehaving a single user actuatable key 657, for example in the form of anon-off key or a bolus key, but no display. The second control unit 660has an entirely different configuration comprising three keys 667 and adisplay 668. The display may provide the user with information as toinfusion settings and/or history, just as the display would allow thecontrol unit to be menu-program mable using the two keys.

[0122]FIG. 7A discloses a control unit 750 mounted in a reservoir unit700. Apart from the outer form of the control unit and the correspondingconfinement in the reservoir unit, the units are of the same generalconfiguration as the embodiment shown in FIG. 3B to which reference ismade. FIG. 7B shows the combined infusion device of FIG. 7A with ahollow infusion needle 701 attached in communication with an outlet fromthe pump or reservoir means and protruding from the lower surface of thereservoir unit. The lower surface is further provided with a peelableliner 702 covering an adhesive layer for attaching the device to theskin of the user. To facilitate introduction of the needle, thedisposable device may be provided with user actuatable means forautomatically advancing the needle into the skin after the device hasbeen attached. FIG. 7C shows the infusion device of FIG. 7B with aninfusion catheter attached in communication with an outlet from the pumpmeans. The infusion catheter comprises an infusion line or tubing 710communicating with an infusion needle 711, a pad 712 being providedbetween the line and the needle, the pad allowing the catheter andneedle to be gripped during the insertion procedure just as it allowsthe catheter to be properly secured to the skin of the user.

[0123] The reservoir unit may be provided with an outlet opening in thevicinity of the lower surface thereof comprising a connector allowingeither an infusion needle or an infusion catheter to be attached to theopening. Such a connector may also serve as a port for filling thereservoir, either initially or during re-filling.

[0124] While the present invention has been described in connection withthe exemplary embodiments shown in the various figures, the deliverysystem according to the invention may be provided with additionalfeatures providing improved functionality, control and ease of use.

[0125] For example, a sensor may be provided for continuously measuringthe pressure in the infusion line or needle, this allowing the detectionof a malfunctioning which could be used to initiate an alarm making theuser aware of a problem.

[0126] However, more advanced sensors may be incorporated in the units.For example, it may be desirable to automatically deliver certain drugsonly when required by the subject, either by patient activation orpassively, such as by a feedback mechanism. In such a case, the devicefurther includes a sensor (feedback) for detecting a condition in thebody of the subject and for controlling the delivery of the drug inresponse thereto. The sensor may be, for example, a temperature sensor,a pulse rate sensor, a blood glucose sensor, a blood pressure sensor ora pH sensor. The sensors may be formed integrally with the reservoirunit or attached separately. The sensor may rest against the skin, maybe inserted through the skin, or may be within the device and separatefrom the skin.

[0127] The reservoir unit may also include a plurality of drugreservoirs, each reservoir being independently controllable andcommunicating with an outlet with which a single infusion needle alsocommunicates. For such a plurality of drug reservoirs, pump meansintegrally formed with the reservoir is preferred, for example in theform of individual gas generators. Including a plurality of drugreservoirs provides for considerable variations in the amounts of drugwhich can be delivered, in the rates at which drug can be delivered andin the number of drugs which can be delivered by the same device. Thereservoir unit may further be provided with a reservoir for acalibrating liquid in case the unit is provided with sensors requiringsuch a liquid.

[0128] In the above description of the exemplary embodiments, thedifferent structures providing mechanical, electrical and fluid contactand communication between the different components just as the meansproviding the described functionality for the different components (i.e.pump, reservoir, energy source, memory, control, display etc.) have beendescribed to a degree to which the concept of the present invention willbe apparent to the skilled reader. The detailed construction andspecification for the different components are considered the object ofa normal design procedure performed by the skilled person along thelines set out in the present specification.

We claim:
 1. A system for delivering a drug to a user, comprising: areservoir unit, a control unit, and at least one further reservoir unitor control unit, each reservoir unit being adapted to receive at leastone control command from a control unit and perform an action inresponse thereto, each reservoir unit comprising: a reservoir adapted tocontain a liquid drug and comprising, in a situation of use, associatedoutlet means, receiving means for receiving the at least one controlcommand, and means for performing at least one action in response to acontrol command, the system comprising expelling means for expelling adrug out of the reservoir through the outlet means, each control unitcomprising: control means providing one or more control commands forcontrolling the operation of a reservoir unit, wherein each combinationof a reservoir unit and a control unit is adapted to provide a systemwith different capabilities.
 2. A system as defined in claim 1,comprising a reservoir unit and at least first and second control units,the reservoir unit comprising: a reservoir adapted to contain a liquiddrug and comprising, in a situation of use, associated outlet means,expelling means for expelling a drug out of the reservoir through theoutlet means, local processor means providing a number of localcommands, means for performing at least one action in response to alocal command, at least the first and second control units eachcomprising: control means providing one or more control commands forcontrolling the operation of the local processor means, wherein eachcontrol unit is adapted to control a different local command orcombination of local commands, thereby providing each combination of thereservoir unit and a control unit with different capabilities.
 3. Asystem as defined in claim 1, comprising a reservoir unit and at leastfirst and second control units, the reservoir unit comprising: areservoir adapted to contain a liquid drug and comprising, in asituation of use, associated outlet means, expelling means for expellinga drug out of the reservoir through the outlet means, local processormeans providing a number of local commands including at least onecommand controlling the expelling means, at least the first and secondcontrol units each comprising: control means providing one or morecontrol commands for controlling the operation of the local processormeans, wherein each control unit is adapted to control a different localcommand or combination of local commands including at least one commandcontrolling the expelling means, thereby providing each combination ofthe reservoir unit and a control unit with different capabilities.
 4. Asystem as defined in claim 1, comprising a reservoir unit and at leastfirst and second control units, the reservoir unit comprising: areservoir adapted to contain a liquid drug and comprising, in asituation of use, associated outlet means, the reservoir unit beingadapted to receive at least one control command from a control unit andperform an action in response thereto, the system comprising expellingmeans for expelling a drug out of the reservoir through the outletmeans, each control unit comprising: control means providing one or morecontrol commands, preferably including at least one control commandcontrolling the expelling means, wherein each control unit is adapted toprovide a different control command or combination of control commands,thereby providing each combination of the disposable unit and a controlunit with different capabilities.
 5. A system as defined in claim 4,wherein the reservoir unit comprises local processor means and at leastone electronically controllable element associated with the localprocessor means, the local processor means being controllable by atleast one control unit.
 6. A system as defined in claim 2, wherein thereservoir unit comprises: local receiving means cooperating with thelocal processor means for receiving control commands from at least onecontrol unit, at least one of the control units comprising: controlprocessor means, control transmission meanscooperating with the controlprocessor means for transmitting control commands to the local receivingmeans for controlling a local command or a combination of localcommands.
 7. A system as defined in claim 2, wherein the reservoir unitcomprises: local transmission means cooperating with the local processormeans for transmitting data information to control receiving means in atleast one control unit, at least one of the control units comprising:control receiving means cooperating with control processor m eans forreceiving data information from the local processor.
 8. A system asdefined in claim 6, wherein at least one transmission means and thecorresponding receiving means are adapted for wireless transmission ofcommands or data information.
 9. A system as defined in claim 2, whereinthe reservoir unit and at least one control unit comprise matingcoupling means so as to allow the control unit to be secured to thedisposable unit, the mating coupling means including communication meansallowing information to be transferred.
 10. A system as defined in anyof claims 2, wherein the reservoir unit and at least one control unitcomprise mating coupling means so as to allow the control unit to besecured to the disposable unit, the mating coupling means includingcommunication means comprising one or more of electrical contacts means,opto-electrical means, wireless transmission means, or mechanicalcontact means allowing information to be transferred.
 11. A system asdefined in claim 8, wherein at least one control unit comprises anattachable subunit and a remote subunit, the subunits comprisingtransmission means and corresponding receiving means adapted forwireless transmission of commands or data information to and/or from therespective unit(s), the reservoir unit and the attachable subunitcomprising mating coupling means so as to allow the attachable subunitto be secured to the reservoir unit, the mating coupling means includingcommunication means allowing commands or data information to betransferred, whereby commands or data information to and/or from thereservoir unit can be transmitted wireless between the remote subunitand the reservoir unit.
 12. A system as defined in claim 1, comprisingat least first and second reservoir units and a control unit, at leastthe first and second reservoir units each comprising: a reservoiradapted to contain a liquid drug and comprising, in a situation of use,associated outlet means, expelling means for expelling a drug out of thereservoir through the outlet means, local processor means providing oneor more local commands, wherein each reservoir unit provides a differentcombination of local commands, means for performing at least one actionin response to a local command, the control unit comprising: controlmeans providing one or more control commands for controlling theoperation of the local processor means, wherein the control means isadapted to control, at least partially, the different combinations oflocal commands, thereby providing each combination of a reservoir unitand the control unit with different capabilities.
 13. A system asdefined in claim 1, comprising at least first and second reservoir unitsand a control unit, at least the first and second reservoir units eachcomprising: a reservoir adapted to contain a liquid drug and comprising,in a situation of use, associated outlet means, expelling means forexpelling a drug out of the reservoir through the outlet means, localprocessor means providing one or more local commands, at least one localcommand controlling the expelling means, wherein each reservoir unitprovides a different combination of local commands, the control unitcomprising: control means providing one or more control commands forcontrolling the operation of the local processor means, wherein thecontrol means is adapted to control, at least partially, the differentcombinations of local commands including at least one local commandcontrolling the expelling means, thereby providing each combination of areservoir unit and the control unit with different capabilities.
 14. Asystem as defined in claim 1, comprising at least first and secondreservoir units and a control unit, each reservoir unit comprising: areservoir adapted to contain a liquid drug and comprising, in asituation of use, associated outlet means, each reservoir unit beingadapted to receive at least one control command from the control unitand perform an action in response thereto, the system comprisingexpelling means for expelling a drug out of the reservoir through theoutlet means, the control unit comprising: control means providing anumber of control commands, preferably including at least one controlcommand controlling the expelling means, whereby each combination of adisposable unit and the control unit is provided with differentcapabilities.
 15. A system as defined in claim 14, wherein at least onereservoir unit comprises local processor means and at least oneelectronically controllable element associated with the local processormeans, the local processor means being controllable by at least onecontrol unit.
 16. A system as defined in claim 12, wherein at least oneof the reservoir units comprises: local receiving means cooperating withthe local processor means for receiving control commands from thecontrol unit, the control unit comprising: control processor means,control transmission means cooperating with the control processor meansfor transmitting control commands to the local receiving means forcontrolling a combination of commands.
 17. A system as defined in claim12, wherein at least one reservoir unit comprises: local transmissionmeans cooperating with the local processor means for transmitting datainformation to control receiving means in the control unit, the controlunit comprising: control receiving means cooperating with the controlprocessor means for receiving data information from a local processor.18. A system as defined in claim 16, wherein at least one transmissionmeans and the corresponding receiving means are adapted for wirelesstransmission of commands or data information.
 19. A system as defined inclaim 12, wherein at least one reservoir unit and the control unitcomprise mating coupling means so as to allow the control unit to besecured to the disposable unit, the mating coupling means includingcommunication means allowing information to be transferred.
 20. A systemas defined in claim 18, wherein at least one reservoir unit and thecontrol unit comprise mating coupling means so as to allow the controlunit to be secured to the disposable unit, the mating coupling meansincluding communication means comprising one or more of electricalcontacts means, opto-electrical means, wireless transmission means, ormechanical contact means allowing information to be transferred.
 21. Asystem as defined in claim 12, wherein the control unit comprises anattachable subunit and a remote subunit, the subunits comprisingtransmission means and corresponding receiving means adapted forwireless transmission of commands or data information to and/or from therespective unit(s), at least one reservoir unit and the attachablesubunit comprising mating coupling means so as to allow the attachablesubunit to be secured to the reservoir unit, the mating coupling meansincluding communication means allowing commands or data information tobe transferred, whereby commands or data information to and/or from thereservoir unit can be transmitted wirelessly between the remote subunitand the reservoir unit.
 22. A system as defined in claim 1, comprisingat least first and second reservoir units and at least first and secondcontrol units, at least the first and second reservoir units eachcomprising: a reservoir adapted to contain a liquid drug and comprising,in a situation of use, associated outlet means, expelling means forexpelling a drug out of the reservoir through the outlet means, localprocessor means providing one or more local commands, wherein eachreservoir unit provides a different combination of local commands, meansfor performing at least one action in response to a local command, atleast the first and second control units each comprising: control meansproviding one or more control commands for controlling the operation ofa local processor means, wherein the control means is adapted to controldifferent commands or, at least partially, different combinations ofcommands, thereby providing each combination of a reservoir unit and acontrol unit with different capabilities.
 23. A system as defined inclaim 1, comprising at least first and second reservoir units and atleast first and second control units, at least the first and secondreservoir units each comprising: a reservoir adapted to contain a liquiddrug and comprising, in a situation of use, associated outlet means,expelling means for expelling a drug out of the reservoir through theoutlet means, local processor means providing one or more localcommands, at least one local command controlling the expelling means,wherein each reservoir unit provides a different combination of localcommands, at least the first and second control units each comprising:control means providing one or more control commands for controlling theoperation of a local processor means, wherein the control means isadapted to control different local commands or, at least partially,different combinations of local commands including at least one localcommand controlling the expelling means, thereby providing eachcombination of a reservoir unit and a control unit with differentcapabilities.
 24. A system as defined in claim 1, comprising at leastfirst and second reservoir units and at least first and second controlunits, each reservoir unit comprising: a reservoir adapted to contain aliquid drug and comprising, in a situation of use, associated outletmeans, each reservoir unit being adapted to receive at least one controlcommand from a control unit and perform at least one action in responsethereto, the system comprising expelling means for expelling a drug outof the reservoir through the outlet means, each control unit comprising:control means providing one or more control commands, preferablyincluding at least one control command controlling the expelling means,wherein each control unit is adapted to provide a different controlcommand or combination of control commands, thereby providing eachcombination of a reservoir unit and a control unit with differentcapabilities. 25 A system as defined in claim 24, wherein the reservoirunit comprises local processor means and at least one electronicallycontrollable element associated with the local processor means, thelocal processor means being controllable by at least one control unit.26 A system as defined in claim 22, wherein at least one of thereservoir units comprises: local receiving means cooperating with thelocal processor means for receiving control commands from the controlunit, at least one of the control units comprising: control processormeans, control transmission means cooperating with the control processormeans for transmitting control commands to a local receiving means forcontrolling a combination of commands.
 27. A system as defined in claim22, wherein at least one reservoir unit comprises: local transmissionmeans cooperating with the local processor means for transmitting datainformation to control receiving means in the control unit, at least onecontrol unit comprising: control receiving means cooperating with thecontrol processor means for receiving data information from a localprocessor.
 28. A system as defined in claim 27, wherein at least onetransmission means and the corresponding receiving means are adapted forwireless transmission of commands or data information.
 29. A system asdefined in claim 22, wherein at least one reservoir unit and at leastone control unit comprise mating coupling means so as to allow a controlunit to be secured to a disposable unit, the mating coupling meansincluding communication means allowing information to be transferred.30. A system as defined in claim 22, wherein at least one reservoir unitand at least one control unit comprise mating coupling means so as toallow a control unit to be secured to a disposable unit, the matingcoupling means including communication means comprising one or more ofelectrical contacts means, opto-electrical means, wireless transmissionmeans, or mechanical contact means allowing information to betransferred.
 31. A system as defined in claims 22, wherein at least onecontrol unit comprises an attachable subunit and a remote subunit, thesubunits comprising transmission means and corresponding receiving meansadapted for wireless transmission of commands or data information toand/or from the respective unit(s), at least one reservoir unit and theattachable subunit comprising mating coupling means so as to allow theattachable subunit to be secured to the reservoir unit, the matingcoupling means including communication means allowing commands or datainformation to be transferred, whereby commands or data information toand/or from the reservoir unit can be transmitted wireless between theremote subunit and the reservoir unit.
 32. A system as defined in anyone of the previous claims, wherein at least one unit further comprisesdisplay means associated with and controlled by processor means.
 33. Asystem as defined in claim 32, wherein at least one reservoir unit is inthe form of a disposable, prefilled unit.
 34. A system as defined inclaim 32, wherein at least one reservoir unit comprises a sensor,preferably associated with a local processor means.
 35. A system asdefined in claim 32, wherein at least one reservoir unit comprises asurface configured to be arranged against a skin surface of a user, thesurface preferably comprising an adhesive means for attaching thereservoir unit to the skin of the user.
 36. A system as defined in claim32, further comprising a sensor for continuously measuring a pressureassociated with the outlet means.
 37. A system as defined in claim 36,further comprising a sensor for detecting a condition in the body of theuser, and means for controlling the delivery of the drug in responsethereto.
 38. A system as defined in claim 32, wherein at least onecontrol unit comprises memory means.